Ron_Adam wrote:
>
> So I didn't know I could do this:
>
> def foo(a1):
> def fee(a2):
> return a1+a2
> return fee
>
> fum = foo(2)(6) <------ !!!
Ah, so you did not know functions are objects just like numbers,
strings or dictionaries. I think you may have been influenced by other
languages where there is a concept of static declaration of functions.
The last line can be better visualized as:
fum = (foo(2)) (6)
where foo(2) is a callable.
-----------
Since a function is an object, they can be assigned (rebound) to other
names, pass as parameters to other functions, returned as a value
inside another function, etc. E.g.:
def g(x):
return x+3
h = g # <-- have you done this before? assignment of function
print h(1) # prints 4
def f(p):
return p # <-- function as return value
p = f(h) # <-- passing a function object
print p(5) # prints 8
Python's use of "def" keyword instead of the "=" assignment operator
makes it less clear that functions are indeed objects. As I said
before, this is something to think about for Python 3K (the future
version of Python.)
------------
Function modifiers exist in other languages. Java particularly is
loaded with them.
public static synchronized double random() {
...
}
So your new syntax:
@decorator(a1)(foo)
def foo():
pass
is a bit out of the line with other languages.
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